Seems like you could put a few of these on a contact lens and minimally get a small private HUD. Seems like with a few of them (or fast enough scanning speed) you could build effectively a light field to give it depth)
I wonder if this has implications for custom home chips/prototyping. I'm sure a big issue is vibrations but something like this could remove the need for masks at least. (again, not my area so I am clobbering terminology I am sure). It may open up home fab capabilities.
I think abusing a write-off electron microscope to side step the need for masks is also an interesting idea, however, I believe acquiring wafers of sufficient quality and depositing layers to be etched could be the bigger challenge here.
This reminds me of the original patents that Magic Leap had, which involved pumping light through a single optical fiber that was wiggled by piezoelectrics into a spiral to project light (https://kguttag.com/2018/01/06/magic-leap-fiber-scanning-dis...).
Seems what it is, but with a "waveguide" instead of an "optical fiber" wiggling about. Seems like a sneaky use of the word "projection" though, since the "surface" the image is "projected" onto is just what the flopping waveguide head traces.
> The chip projected a roughly 125-micrometer image of the Mona Lisa.
This may seem small (barely visible as a dot to the naked eye), but that's also the geometric mean of the Planck length and the diameter of the observable universe. So average size actually.
They mean 125um = sqrt(a*b), where a is the Planck length* and b the size of the observable universe (I didn't verify). Implying, 125um is some sort of middle ground.
*Often said to be the smallest length with physical meaning.